Copolymers of vinylidene cyanide with alkyl acrylates



Patented Oct. 28, 1952 UNITED STATES PATENT OFFICE Vernon L. Folt, Akron, vhio,.assignor.'to Th'e'IS. Goodrich Company, New York, N. Y., a corporation of New York Nb Drawing. Application October 17, 1950, Serial No. 192.636 8 Claims. (01. 26648.5)

This invention relates to the preparation; of novel copolymers of vinylidene "cyanide with alkyl esters of acrylic acid, which copolymers are useful resinous materials, being especially valuable in the preparation of filaments, films andmolded articles. 7

In U. S. Patents 2,476,270 and 2,502,412, to Alan E. Ardis, and 2,514,387, to Harry Gilbert, novel methods for the preparation of monomeric vinylidene cyanide are disclosed." In a copending application, Serial No. 11,336; filed February 26, 1948-, methods for the preparation of useful homopolymers of vinylidene cyanide are dis closed.

Monomericvinylidenecyanide is a clear liquid at room temperature and a crystalline solidat 0 C}; it meltsin the range of 610 to 9.'7 G, depending o n.,pu-rity-, withpurestsamples melting at 9-0 to 9.7 (3-. and it boils at 40? G; at areduced pressure of mm. of mercury. It is quite unstable because of its extreme sensitivity to water, undergoing on contact with water at room temperature an instantaneous homopolymerization reaction to give a solid water-insoluble resin. When it is allowed to standat room temperature in admixture with butadiene- 1,3, it reacts therewith to give solid 4,4-dicyanocyclohexene.

It has now been discovered that monomeric vinylidene cyanide of the above physical and chemical properties will copolymerize with alkyl esters of acrylic acid in the presence of a .free radical catalyst.

The alkyl acrylates which are polymerized with vinylidene cyanide in accordance with'the present invention possess the structure CHa CHCOOR wherein "R is an alkyl radical. Included within this class of compounds are: methyl acrylate, ethyl acrylate, propyl acrylate, isop'ropyl acrylatebutyl acrylate, isobutyl' acrylate, amyl ae'rymte, hexyl acrylate, Z-ethyl hex'y'l acrylate, heptyl acrylate, octyl acrylate, iso'nonyl acrylate, 3,5,5-tr'imetliyl hexyl acrylate, "decyl acrylate, dode'cy'l acrylate, and the like, with the particularly preferred alkyl acrylates being those in which the radical R contains from one to teii carbon atoms, r V Y H The polymerization itself may be carried out in several different ways. For example, one pie ferred method consists simply in heating a mix: ture of the monomers and polymerization catalyst, without the use of a solvent or other liquid medium for the monomers, to eiiect the polymerization. The polymerization occurs readily at temperatures of about C.- to 100 C), the copolymer forming generally as a white resinous powder of small particle size.

Asec'ond method of polymerization consists n first dissolving the vinylidene cyanide" and alkrl r t i b ne or o her iqu d e e- Inatic solvent such as, toluene, methyl toluene, qr zene... o he ,li a pr erebl irs m. m r t es, wh h in t at t e i ih r r a n 9f he m qmer ad 1 1 amoun f t at t e solven compr es. a e ox ma' y 30% to by weight of the total solution. A polymerization catalyst is included in the solution and the resulting mixture is maintained at the desired temperature, whereupon polymerization occurs to form the desired copolymer. The copolymer thus formed may be separated from the polymerization medium simply by filtering, or, if desired, the solvent may be removed by evaporation. Also, the polymerization may be efiected at temperatures as low as 0 C. or lower, or as high as C. or even higher, provided a catalyst is utilized which will dissociate into free radicals at the polymerization temperature.

The respective quantities of the alkyl acrylate and vinylidene cyanide in any polymerization chargeare'not critical sincea useiulcopolymer is obtained regardless of the amount oi either monomer in the charge, a s will be demonstrated h x p r i .QW.-,..Th ram l l. i

vinylidene cyanide in the monomercharge may be as low as Olmole per cent or as high as 99 mole per cent while obtaining copolymers markedly different from straight homopolymers of either the alkyl acrylate or the vinylidene cya- Ilid;

his to be understood, of course-that regardless of the pelyinerizatioii method utilized, the polymerization should be stopped before either of the monomers is entirely consumed, in order that true copolymer, will be obtained. Otherwise, when either of the monomers is completely used up, the product will containstraight polymer obtained by polymerization of the remaining monomer. Accordingly,,it is often desirable to add, c'onunuou'sm qr termittentl fresh quantities of one oi bothof the monomers, and also of catalyst and solvent, if desired, to the polymerization mixture during the course of the polymerization, thus taking fullest advantage of thecapacity of the equipment and ineffect operating, a continuous or semi-continuous es' The ctalyst which. is iised in the poiymeri zation process is pr y a peroxygen com pound, such as, silver peroxide, the perme tes, the perca'rbonates, benzo'yl peroxide; caproyl peroxide, lauroyl peroxide; acetone peroxide. acetyl benzoyl peroxide, cun'iene hydroperoxide, o,o'-'dichlorobenzoyl peroxide, o,o"-dibromoben'- zoyl peroxide, capr'ylyl peroxide pelargonyl peroxide, tertiary butyl hydroperoxide, tetralinperoxide, and thelike. In general, from 0;01 t0 2 b wa the: s amstress on he weight (if the monomers, is utilized, although 3 Smaller or larger amounts may b utilized, if desired.

The following examples illustrate the preparation of copolymers of vinylidene cyanide with ing within the spirit and scope of the appended claims. 1

I claim: 1. A two component copolymer of monomeric alkyl acrylates in accordance with this invenvinylidene cyanide and an alkyl ester of acrylic tion, but are not to be construed as a' limitation I acid, said copolymer being a resinous, heatupon the scope thereof, for there are, of course, softenable solid which is insoluble in acetone, numerous possible variations and modifications. the monomeric vinylidene cyanide entering into 1 saidcopolymer to produce vinylidene cyanide EXAMPLES I To VI units being a liquid at room temperature and a A series of ix vi ylid cyanide-n-butyl crystalline solid at 0 0. having a melting point acrylate copolymers is prepared by mixing varywhen in purest form of substantially 9.0 to 937 ing amounts of both monomers with 0.15% (based a d being Characterizable chemically by t on the total weight of the two monomers) of a y o undergo 011 C nt t With Water at room o,o-dichlorobenzoyl peroxide and maintaining temperatu E a instantaneous p y the resulting mixtures at a temperature of about tion reaction to give a'solid,-water-insoluble resin 50 C. for a period of several hours. The hard, and bythe ability to react at room temperature resinous copolymer obtained at the end of this with butadiene1,3 to g ve Solid 4,4edicyanocyclfi4-v period is then analyzed to determine its comheXene 1 f position. The mole per cent of vinylidene cyanide The copolymer of claim 1 wherein the 57 in the polymerization charge n t mole radical of the alkyl ester of acrylic acid contains cent of vinylidene cyanide in the resulting cofrom 1 to 10 carbon atoms. I polymer are recorded in the following table: he op y e of claim 1 w e the alkyl Table I ester of acrylic acid is n-butyl acrylate.

' 5 4. The copolymer of claim 1 wherein the alkyl ester of acrylic acid is. methyl acrylate. lVl/ole 1: am Ag le llegcent 5. The method which comprises admixing $1 5,32 ,315, 5 liquid monomeric vinylidene cyanide, said mon- Charged copolymer omeric vinylidene cyanide being characterizable chemically by the ability to undergo on contact g with water at room temperature an instantaneous homopolymerization reaction to give a solid, water-insoluble resin and bythe ability to react' 92:0 at room temperature with butadiene-LS togiv'e 5 solid 4,4-dicyanocyclohexene, with an alkyl ester EXAMPLES VII To XIV of acrylic acid, and with a peroxygen catalyst in an amount from 0.01 to 2.0% by weight of the ples I to VI are repe ted u izing methyl monomers, and maintaining the resulting mix acrylat in place of the n-butyl acrylate. A hard, ture at a temperature of from 0- C. to 100 0., resinous copolymer which is compl ely insoluble 40 thereby to form a solid resinous, two component, in acetone is obtained. The pertinent data is acetone insoluble copolymer of vinylidene cyanide tabulated below: with said alkyl ester of acrylic-acid.

Table II J Mole Percent Percent Mole Percent Example vinyl dene Time Percent Con- Nitmgenm vinyl dene cyafiiggem (Hours) A version copolymer 85301111331 1511 57 488 23. 5 5. 74 1s. 01 as. 540 5. 488 as. 5 5. 35 11. 15 as. 201 10.919 33.5 5. 94 14.52 43.033 15. 295 as. 5 5. so .18. 01 52. 523 26.886 33.5 287 20.59 50.015 52. 453 27. 0 5. 20 23. 57. 515 75. 796 27. 0 a. 25. a4 72. 587 so. 849 29. o 2. 5o 29. 0o 82. 265

When other alkyl acrylates selected from those 6. The method of claim 5 wherein the alkyl disclosed hereinabove are substituted for n-butyl radical of the alkyl ester of acrylic acid 5011- acrylate or methyl acrylate in the above extains from 1 to 10 carbon atoms. amples, the copolymers obtained are also hard, '7. The method of claim 6 wherein the alkyl resinous materials which are completely insoluble ester of acrylic acid is n-butyl acrylat'e and the, in acetone. Likewise, when the polymerization 6O peroxygen catalyst is o,o'-dichlorobenzoyl chlo-i is carried out according to the other methods ride. V described hereinabove, or utilizing other of the 8. The method of claim fiwherein the alkyl peroxygen catalysts disclosed, excellent results ester of acrylic acid is methyl acrylate and'the' are achieved. From the examples it is found that peroxygen catalyst is -o,o di chlorobenzoyl per-1 copolymers of alkyl acrylates with vinylidene oxide. f cyanide are more thermoplastic than straight VERNON L. FOLT. homopolymers of vinylidene cyanide and yet are harder than straight polymers of the alkyl acry- REFERENCES CITED lates, thus demonstrating the unique properties The f ll i feren e are of mcordmthe obtained by copolymerizing the two types of fil of this t t; monomers of the present invention.

Although specific examples of the invention UNITED STATES PATENTS have been herein described, it is not intended Number Name Date to limit the invention solely thereto, but to in- 2,396,785 'Hanford Mar.1 9,1946 r-mde all of the variations and modifications fall- 7 2,466,395 Dickey Apr. 5, 1949 

1. A TWO COMPONENT COPOLYMER OF MONOMERIC VINYLIDENE CYANIDE AND AN ALKYL ESTER OF ACRYLIC ACID, SAID COPOLYMER BEING A RESINOUS, HEATSOFTENABLE SOLID WHICH IS INSOLUBLE IN ACETONE, THE MONOMERIC VINYLIDENE CYANIDE ENTERING INTO SAID COPOLYMER TO PRODUCE VINYLIDENE CYANIDE UNITS BEING A LIQUID AT ROOM TEMPERATURE AND A CRYSTALLINE SOLID AT 0* C. HAVING A MELTING POINT WHEN IN PUREST FORM OF SUBSTANTIALLY 9.0* TO 9.7* C. AND BEING CHARACTERIZABLE CHEMICALLY BY THE ABILITY TO UNDERGO ON CONTACT WITH WATER AT ROOM TEMPERATURE AN INSTANTANEOUS HOMOPOLYMERIZATION REACTION TO GIVE A SOLID, WATER-INSOLUBLE RESIN AND BY THE ABILITY TO REACT AT ROOM TEMPERATURE WITH BUTADIENE-1,3 TO GIVE SOLID 4,4-DICYANOCYCLOHEXENE 